1. Field of the Invention
The present disclosure is related to the disclosures provided in the following U.S. applications filed concurrently herewith: "A Device For Driving Inserts Into Pieces Of Sheet Metal", filed in the names of M. SCAVINO et al. (U.S. Ser. No. 08/613,142); and "A Machine And A Method For Driving Inserts Into Pieces Of Sheet Metal", filed in the name of K. ITO (U.S. Ser. No. 08/63,171); and the disclosures of the aforementioned applications are hereby expressly incorporated by reference herein in their entireties.
The present invention is related to a machine and to a method for driving inserts into pieces of sheet metal.
2. Description of Background Information
In the field of the production of elements formed by bent or pressed metal sheets, there is often a need to form threaded or non-threaded fixing or anchoring points on the internal or external surface of the sheet-metal element. This need is experienced particularly in the case of aluminum sheets in which it is difficult to produce threaded holes because of the mechanical properties of aluminum.
The inserts are generally formed of metal and are driven into preformed holes in sheets of metal (aluminum, steel or other materials). The inserts may be of various shapes and dimensions according to the function which they are intended to perform. The most common inserts have a hole or a shank which is generally threaded in order to form anchor equipment, components and the like to the sheet metal, by screwing the equipment, component or the like to the metal sheet via the insert.
A press is normally used to drive the inserts into the preformed holes in the metal sheets. Generally, the press includes a punch and a die which cooperate with one another, and between which a driving zone is defined. The inserts are anchored to the sheet when they are force-fitted into the respective holes in the sheet, so as to bring about plastic deformation of the portion of the metal sheet adjacent the hole into which the insert is force-fitted.
In the machines currently available, the press is operated manually by an operator who holds the piece of sheet metal during the driving of the inserts and moves the piece after each driving operation. Some machines have an automatic supply device, which generally has vibration feeders that send the inserts to the driving zone by various systems. Devices having the vibration feeder type automatic suppliers are useful only when repeatedly performing insertion of a large number of inserts which are all of the same type and size.
In practice, there is often a need to successively drive a plurality of different inserts, which differ from one another in function, shape or size, into the same piece. When there is such a need, the operator of some known machines must position the inserts in the driving zone of the press manually.
This results in a high labor cost of production, low productivity, a high risk of error and a high risk of accidents to the operator, because of the dangerous nature of the operation.
In cases where machines with automatic insert-supplies are used, it is still necessary to manually empty the insert container and fill it with the new inserts each time a requirement for a different type or size insert is required. Moreover, if the new inserts are significantly different in shape and/or size from the inserts being removed from the container, it is often necessary to replace the supply duct which transfers the inserts from the container to the driving zone.
This results in a long tooling time which makes it economically unfeasible to drive different inserts into the same piece in succession.